Twin lens camera system having sequential or simultaneous lens operation

ABSTRACT

A twin lens camera system for producing multiple photographs from a single film sheet. The system includes a sliding back arrangement for movement of the film sheet so as to present different areas thereof to the twin lenses, and a logic circuit and indicator elements for denoting a suitable operational program of the system. A selector switch provides simultaneous or sequential operation of the twin lens system, and the logic circuit is responsive to either operational mode so as to indicate movement of the film sheet following operation of both lens systems.

United States Patent i n 1 Mar. 12, 1974 i5 1 TWIN LENS CAMERA SYSTEMHAVING 3,558,226 H1971 Riggs 1. 95/37 Q E I L OR SIMULTANEOUS LENS3,128,685 4/1964 Kitrosscr 95/18 2,497,358 2/1950 Huntzinger 95/37OPERATION 3,424,071 1/1969 Schwahn v 95/11.5 [75] Inventor: Myron A.Seiden, Needham, Mass, 3,726,198 4/1973 Bjork 95/18 X [73] Assignee:Polaroid Corporation, Cambridge,

Mass Primary Examiner'-John M. Horan [22] Filed: Sept. 15, 1972 [21]Appl. No.: 289,443 [571 AFSTRACT Related US Application Data A twin lenscamera system for producing multiple photographs from a single filmsheet. The system in- [63] gy sg wg gi gg 35, cludes a sliding backarrangement for movement of I the film sheet so as to present differentareas thereof 1 6 M 554/88 355/53 355/54 354/118 to the twin lenses, anda logic circuit and indicator e1 [5] u G63) ements for denoting asuitable operational program of [58] Fieid 355/53 54 the system. Aselector switch provides simultaneous or I i s sequential operation ofthe twin lens system, and the [56] References Cited logic circuit isresponsive to either operational mode ES P TENTS o as to indicatemovement of the film sheet following UNITED STAT A operation of bothlens systems. 1,820,113 8/1931 Bettini 95/37 11 Claims, 8 DrawingFigures SWPTEH'ES I I 29 L TAB i24) /'i I5 ii ii LENS SELECTOR LOGICCIRCUIT FLASH PUSH Burrow SELECTOR cums: SWII'CH SWITCH (27) (25) (2s)PAIENTEDHAR 1 2 1914 3796; 485

SHEET 1 OF 4 BA K SWITCHES l TAB 22 SWITCH l5 l4 \L H H u-zus SHIFT BACKSELECTOR LOGIC CIRCUIT 16 U T t FLASH PUSH BUTTON SELECTOR CHARGE SWITCHSWITCH (27) (25) (26) PAIENTEDHAR 12 1974 37963185 sum 3 [IF-4 FIGSPAIENTEDMAR 12 I974 3.796.485

- sum u 0F 4 70 I5 l SHIFT BACK 72 I 26 SWITCH (63) ONE SHOT I I3COUNTER i NETWORK 4 FIG. 8

TWIN LENS CAMERA SYSTEM HAVING SEQUENTIAL OR SIMULTANEOUS LENS OPERATIONCROSS REFERENCES TO RELATED APPLICATIONS This application is acontinuation-in-part of US. Pat. application Ser. No. 214,633 of MyronA. Seiden filed on Jan. 3, 1972, now US. Pat. No. 3,760,702 and entitledTWIN LENS CAMERA SYSTEM WITH SLID- ING BACK.

BACKGROUND OF THE INVENTION a single sheet of film. Preferably, itembodies a twin lens camera system which in conjunction with relativemovement between a film sheet and the lenses provides four photographson the single film sheet. In this arrangement, the camera is a so calledSelf-developing Camera System" having a back section, movable betweentwo positions so as to present different areas of the film sheet-to thedual optical system. In operation of the camera system, the back sectionis placed at a first position and the dual optical systems are triggeredto record a pair of images in side by side relation. Thereafter, theback section is moved to its second location where the above step isagain repeated. The film sheet is then withdrawn from the camera througha processing station of the latter. Hence, while the operation of thesystem, like the structure itself is greatly simpli-' fied itnevertheless requires several manual steps in sequence to produce'thedesired multiple photographs.

Consequently, an important object of this invention is to provide animproved camera system having control means for assuring properoperation of the system.

Another important object of this invention is to provide a camera systemcapable of automatically indicating to the operator the properoperational cycle to be followed.

Still another object of this invention is to provide an improved camerahaving a dual lens system capable of either individual or simultaneousoperation responsive to shutter trigger operation.-

A further object of this invention is to provide a dual lens, programindicating camera system capable of either individual or simultaneousoperation of each lens system.

SUMMARY OF THE INVENTION This invention provides a new and useful camerahaving a twin lens system and a sliding back, film sheet holder whichfacilitates the presentation of different areas of the film sheet to thetwin lens system. A control system provides this camera with acombination of a mechanical and electrical logic program of operation,in part automatic, with a bank of indicator lights as part of suchcontrol system, and electrical circuitry as a control element in suchprogram, responsive in part to movement of the sliding back andproviding a selection function as between simultaneous and sequentialoperation of the elements of such twin lens system. In this arrangement,mechanical movement of a film sheet holder, to present difierent areasof the film to a twin pair of optical systems, is combined withelectrical switching as between the optical systems to selectivelyexpose different portions of each of such film areas; such exposurebeing selected as simultaneous or sequential by means of a switchsetting by an operator.

The structure of the herein illustrated embodiment of this inventionincludes a main body camera housing in which a twin pair of opticalsystems is provided as a means of forming images of a subject orsubjects at a focal plane. This arrangement thus can form an image ineach of two side by side portions of one area of a sheet of photographicfilm which is one half of the available area of the film sheet. Attachedto the main housing is a camera back housing, carrying a sheet ofphotographic material at the focal plane, and which is slidable, in itsattachment to the main housing, in a straight line shuttle movementbetween two positions so as to present one half of the available area ofthe sheet to both the optical systems at one of its positions, and topresent the other half of the film at the other position. At each suchposition the selector switch gives the option of simultaneous orsequential operation of the optical systems.

A control system is provided as a means of operating this camera systemon an unidirectional logic program basis to assure proper operation. Inthe illustrated embodiment, this control system includes automaticindicator signals, which, if followed by the operator, will assureproper operation of the camera in a logic cycle of sequentialoperational steps. These signals relate to movement of the camera backbetween. its two positions followingthe taking of two picturesindividually or separately in each respective position, to the operationof electronic flash units used in taking each picmm, and to the pullingofa photographic material pull tab in the course of treatment andremoval of such material from the camera system.

Another form of such control is a selector switch and automaticelectrical circuitry therewith, for establishing the operation of thetwin optical systems as simultaneous or sequential.

BRIEF DESCRIPTION OF THE DRAWINGS The novel features that are consideredcharacteristic of the invention are set forth with particularity in theappended claims. The invention itself, however, both as to itsorganization and its method of operation together with additionalobjects and advantages thereof, will best be understood from thefollowing description of the preferred embodiment when read inconnection with the accompanying drawings wherein like numbers have beenemployed in different figures to denote the same parts and wherein:

FIG. 1 is a schematic illustration of a camera system and a logicprogram'control electrical circuit therefor, according to thisinvention;

FIG. 2 is a front perspective of a camera embodying this invention;

FIG. 3 is a rear perspective of the camera of FIG. 2;

FIG. 4 is a comprehensive showing of much of a camera system embodyingthis invention, in the form of a side elevation, partially cut away andpartially sectional;

FIG. 5 is a fragmentary and cut-away showing of the top portion of asystem according to this invention, in illustration of the camera backmovement spring and a magnet on the control system;

FIG. 6 is a further view of the structure of FIG. 5, additionallyshowing a circuit board for the control systern;

FIG. 7 is a rear view of the back plate of a camera system according tothis invention, with phantom and dotted line showings of associatedstructure; and 7 FIG. 8 is a detailed schematic illustration of the lensselector unit of FIG. 1. Y

DESCRIPTION OF THE PREFERRED EMBODIMENT As illustrated in FIGS. 1-4, thecamera system is based on a pair of lens units 10 and l l as opticalsystem components for forming subject images of a given size at a focalplane 12, at which a sheet of film, also indicated as 12, is mounted.Aligned with the focal plane is a camera back or film sheet holder 42which is configured for up and down sliding movement in the focal plane.A septum 12a is mounted between the lens units 10 and 11 so as toconfine the image rays from each lens to a separate quadrant of the filmsheet 12. As the camera back is moved up and down, see FIG. 4, the filmsheet 12, which is four times the given size of any one image, is alsomoved up and down, at and along the focal plane such that at eitherlocation, one-half of the film sheet is positioned behind the lens units10 and 11 whereby they can form images respectively in these sheetareas. A pair of solenoid operated shutters schematically indicated at18 and 19 in FIG. 1 are used to operate the lens units 10 and 11respectively. A flash illuminator unit 20 and aiming light unit 21 arealso shown in conjunction withthis system.

electronic logic circuitry including directional indicators denotingWAIT, SHIFT BACK and PULL TAB directions is employed in this camerasystem. This circuit while similar to the system described in thecommonly assigned U. S. Pat. application Ser. No. 77,916 of Albion P.Bjork et al. filed Oct. 5, 1970 also includes a lens selector unit 13which, in conjunction with a selector switch 26, provides means forselectively providing simultaneous or sequential operation of the lenssysterns 11 and 12, or more particularly of the shutter devices 18 and19 responsive to actuation of the pushbutton shutter switch 25.

switches-23 which are responsive to the movement of the camera back 42;a tab switch 24 responsive to the action of pulling the film tab; aflash unit 27 in continu- '8) and its output leads 28 and 30, controlboth shutter arrangements 18 and 19 in accordance with operation of thepushbutton switch 25. Triggering of these shutters, in turn, switches ona SHIFT BACK signal 14. The latter is then extinguished upon movement ofthe back to a new location in accordance with operation of the backswitch 63 as later explained in detail in regardto the overall operationof the unit. Additionally, operation of the pushbutton switch 25 firesthe flash charge unit 27. The reduction in charge automatically turns ona WAIT signal 15, and the latter is then extinguished when the chargeagain reaches a suitable level. Finally. as later explained in detailwith regard to the overall operation of the camera system, back switches64 and 65 and the tab switch 24 control the operation of a PULL TABsignal 16.

Referring now to FIG. 8, the selector unit 13 is shown to include a pairof or networks and 72 which control the shutter units 18 and 19,respectively. The input to both devices 70 and 72 are through switch 26.In one position of the latter, as shown in bold lines in this figure,both or devices and hence units 18 and 19 are simultaneously triggeredupon operation of the pushbutton switch 25. At this time, the SHIFT BACKlight which is coupled to shutter 19 is lit so as toindicate that theback should now be displaced to its other location. In the otherposition of the switch 26 (shown dotted) each or network is sequentiallytriggered, re-

sponsive to repetitive actuation of the switch 25,

through a one shot counter network 74, or the like. That is, assumingswitch 26 is in its sequential position, and hence coupled to thecounter 74, the latter operates to first trigger shutter 18 (throughnetwork 70) upon a first operation of the switch 25. Then upon asubsequent operation of the latter switch (to record a second image)shutter 19 is triggered, the counter 74 resets to its initial mode, andthe SHIFT BACK light is lit. Hence, it should be understood that thecircuit 13 in conjunction with the SHIFT BACK indicator instructs theoperator to move the camera back following the taking of both images ona given half of film sheet, and specifically provides means foractuating one of the shutters simultaneously with or subsequent to theother and means for indicating to the operator that the camera backshould be moved responsive solely to actuation of the one shutter.

Prior to completing the description of the camera circuitry and itsoperation, it is advantageous to discuss the external views of FIGS. 2and 3 which show a main body camera housing 34, with the lens units 10and 11 and the flash and aiming light units 20 and 21, in a front panel35. This housing has side handles 36 and a camera operating pushbutton37. FIG. 3, in particular, shows acamera back plate 38 mounted on theback of the main housing 34. A pair of vertical and parallel guide rails39 are mounted on the rear of the back plate 38, withthe top end of aback baffle plate 40 showing parts of side edges 41 out-tumed rearwardlytherefrom. The baffle plate 40 is mounted on the back plate 38 betweenthe guide rails 39. A camera back housing 42 is attached to the mainhousing 34 by being slidably mounted with protruding side edges underthe overhand of the guide rails 39. The back 42 has an openable cover43, hinged at 44. A set .of indicator lights 45 (WAIT, SHIFT BACK, PULLTAB) are mounted on the back plate 38 as is the selector switch 26.

In FIG. 4, a light passage 46 extends from the lens unit 11 (and 10)back through the camera. The passage 46 is divided in two by the septum12A. The back plate 40 and the baffle plate 38 have openingstherethrough in continuance of the passage 46, and divided by a septumextension 47. The back baffle plate 40 has somewhat horizontallyextending baffles 48 and 49. at the top and bottom of the baffle platelight opening. The septum extension 47 and the baffles 48 and 49 extendto a point closely adjacent the film sheet-focal plane 12. Thus a lightpassage to the focal plane is provided from each lens unit and 11 to aquadrant of the film sheet and each quadrant is generally defined bythese baffles, the septum extension and the inner side walls of the backhousing 42. A film pack is indicated at 50, presenting a sheet of filmat the focal plane 12.

Further, in FIG. 4, one of a pair of stop bars 51 is shown, mounted onthe baffle plate 40 and secured to the back plate 38 through mountingbolts extending through the baffle plate. The stop bars 51 limit the upand down movement of the camera back 42. In the up position, as shown,the lower ends of the stop bars 51 engage interior abutments 52 as partof the camera back unit. In the down position of the camera back, thefixed stop bars engage other interior abutments 53 within the cameraback. These stop arrangements assure the alignment of the two halves ofthe photographic sheet with 'the baffle plate light aperture and thusproperly with the lens systems, in each of the two positions of thecamera back. As part of the light barrier system of this device, a pairof cross channels 54 in the sliding face of the camera back 42 havestrips of napped material therein, such as velvet or felt, for sidewayssliding engagement with the rear face of the baffle plate 40, as thecamera back is moved up and down.

Also in FIG. 4, in the back unit, a pair of rollers 55 are shown, forspreading developer fluid over an exposed sheet of film as the film ispulled through the rollers. This structure and the whole camera back isessen- 'tially that of the Polaroid Land Camera back model CBIOOmarketed by Polaroid Corporation of Cambridge, Mass. A pull 'tab isindicated at 56, and a pullpreventer at 56a.

Again in FIG. 4, in the camera back 42 and adjacent the rollers 55, thepull tab switch 24 is shown. Inside the main camera body 34 an extension57 of the pushbutton 37 of FIG. 2, is carried into a switch unit 25,such that the latter is operable in consequence of the up and downmovement of the spring return pushbutton 37.

In FIGS. 5 and 6, a set of overcenter springs 58 is shown. Each is'mounted in a loop form, with one end pivotally secured at 59 to thefront of the back plate 38 and the other end pivotally secured at 60 tothe inner face of the sliding back 42, through a slot6l in the backplate 38. With the camera back 42 in the up position, the springs 58 arein the solid line position shown in FIG. 6 biasing the camera back in aholding effect upwards, with the camera back in the down position, thesprings 58 are in the dotted line position shown, and biasing the cameraback in a'holding effect downwards.

FIG. 6 further shows a circuit board 62 for mounting at least part ofthe logic circuit of this system, including the back switches 23. Thisis a set of need switches. Switch 63 is in the circuit related to theshift back light;- switch 64 is an enabler in the pull tab light system;and switch 65 is an actuator in the pull tab light system. A magnet 66is secured to the camera back through the connector 60 and movestherewith past the reed switches 23 to operate them as the camera backis i moved.

FIG. 7, in further explanation of the structure on the rear of the backplate 38, illustrates the guide rails 39 with phantom indications of thesliding back 42. The

baffle plate 40 and the overcenter springs 58 are also illustratedherein with associated structure.

As previously indicated, the camera system of diis invention is acombination of a pair of optical systems with a film sheet carried in asliding back and a logic program control system. An electrical circuitsystem including a bank of indicator lights is used, in partautomatically, as part of the control program. In this arrangement, thecamera system includes four operator actions: (1) actuation of thepushbutton; (2) movement of the camera back, up and down; (3) themovement. involved in pulling the pull-tab and removing exposed filmfrom the camera; and (4) operation of the selector switch. It involvesone switch in relation to the movement of the camera actuator, threeswitches in relation to the movement of the camera back, one switch inrelation to the pulling of the pull-tab, and the selector switch. Italso involves three indicator lights: (1) WAIT; (2) SHIFT BACK; and (3)PULL TAB.

In operation of the camera, the electronic flash system for each pictureis actuated to discharge as a result of actuating the camera pushbutton.This same action results at least indirectly, in the WAIT light comingon. Subsequently, this light goes out as a result of a sensor responsein a suitable charging circuit for the electronic flash system- If theoptical systems are sequential, this action is then repeated. Operationof both optical systems turns on the SHIFT BACK light'which then goesout as a result of movement of the camera back. Movement of the cameraback to one position (the down position) first enables the PULL TABlight circuit, and further movement of the camera back (following lensactuation) to the other position (the up position) turns on this lightwhich is then turned out responsive to actuation of the pull-tab switchin the course of removing the exposed film from the camera when thepulltab is pulled.

Assuming a starting situation is with the camera back 42 and its filmsheet 12 in the up position and all lights out, if the selector switchis in position for simultaneous operation of the lens units 10 and 11,when the pushbutton 37 is depressed (closing switch 25) and both shuttermechanisms 18 and 19 are triggered and the flash system is discharged soas to simultaneously record two images, side by side, of the scene. Atthis time, the WAIT and SHIFT BACK lights 14 and 15 come on. The WAITlight 14 is a control signal to refrain from depressing the pushbuttonuntil the charge circuit reaches a suitable level while the SHIFT BACKlight 15 indicates a new half of the film should be presented to thelens units 10 and 11. In sequential lens unit operation, only one lensunit is used at a time, and only the The electrical system readjusts sothat the next depression of the pushbutton 37 will only actuate thefirst lens unit (assuming the selector switch 26 is left in itssequential" position). The control direction, however, is to both movethe back to its new location and to also refrain from actuating thepushbutton 37 until the WAIT light 14 again goes out. The SHIFT BACKlight actuated to enable or activate, the PULL TAB light circuitincluding the switch 64.

In the down position of the camera back, the lens units and 11 are againoperated, either simultaneously or sequentially in the same manner andwith the same control effects as in the up position of the back. Thus,once both lens units have been operated in the down position, and theWAIT light has been on either once or twice according to the setting ofthe selector switch 26, the SHIFT BACK light 15 is again automaticallytriggered. This indicates to the operator that the camera is again to bemoved, this time back to its up position. During this movement, as themagnet passes the' new enabled switch 64, that switch is actuated, andthe PULL TAB light 16 comes on. As the magnet further rises and passesthe switch 63, that switch is again actuated to extinguish the SHIFTBACK light 15. When the back is in its up position and the tab 56 ispulled in accordance'with the indicator light and in preparation forremoval of the film sheet, the switch 24 is automatically triggered soas to extinguish the PULL TAB light 16.

Consequently, the camera system provides a simple logic arrangement andinstructional operating indicia adapted for separately recording fourimages on two pairs of imagesfThe logic system and its instructionalindicia, which automatically directs the operator through apreprogrammed sequence of steps, is converted from image taking mode tothe other by single switch, and advantageously may be altered followingthe taking of any two side-by-side images.

Hence, this invention includes a unique system of control which is acombination of automatic and man-.

ual control, and a combination of a mechanical iterative logic program(the back movement) and, when selected, a basically electrical iterativelogic program of sequential operation of the lens units. The programthus is one iterative logic sequence with an optional nesting therein ofa local interpolation of another iterative logic sequence which presentsa highly controlled, highly versatile system.

This invention therefore provides a unique and useful camera system forproducing more than one photograph from a singlesheet of photographicmaterial and comprises a twin lens system with a'film sheet carried in amovable back and a control logic program which is versatilein offering aselection of different programs by operator choice and simple selectionaction, such selection being available twicein one sequence, once ateach of the positions of the camera back. These programs are essentiallymanually initiated, with automatic system aid in completion including abank of indicator lights which provide directives of action ornon-action in a system of programmed control.

As many embodiments may be made of the above invention and as changesmay be made in the embodiment set forth above without departing from thescope of the invention, it is to be understood that all matterhereinbefore set forth and in the accompanying drawings is to beinterpreted as illustrative only and not in a limiting sense.

What is claimed is:

i. A camera system comprising:

a pair of optical systems for respectively transmitting image carryingrays along a pair of exposure paths so as to form a pair of images of agiven size at a focal plane;

means for mounting a sheet of photographic material in said focal plane,such photographic sheet being at least four times said given size;selectively operable shutter means for unblocking and then blocking eachof such exposure paths;

means for actuating said shutter means to substantially simultaneouslyor sequentially unblock and block each of such exposure paths wheneither a first or second area of such photographic sheet is located inoperative relation to said'optical systems;

means for achieving relative movement between said optical systems andsaid mounting means to sequentially present such first and second areasof such sheet of photographic material to said optical systems wherebysuch a first area may be first exposed to record a pair of imagesthereon and, after relative movement has been'effected between saidoptical systems and said mounting means, such second area may be exposedto record a second pair of images thereon, the normal operation of saidcamera system being devised to commence with said mounting means in afirst given position with respect to said optical systems'and involvinga predetermined sequence of steps performed by an operator to produce apair of images on each such first and second areas of such photographicsheet, said sequence of steps including one step of operating saidshutter actuating means so as to record a first pair of images and asubsequent step of effecting relative movement between said opticalsystems and said mounting means following the operation of said shuttermeans; and

means responsive to the performance by the operator of said one step forindicating to the operator that said subsequent step is to be taken byhim in conforming with said predetermined sequence of steps.

2. The camera system of claim 1 wherein said shutter means includes apair of shutters, and said actuating means includes means for actuatingsaid shutters, and wherein said means for indicating is responsive toactuation of both said shutters.

3. The camera system of claim 1 wherein said actuating means includesmeans for actuating one of said shutters simultaneously with, orsubsequent to, the other of said shutters and wherein said indicatingmeans is responsive solely to actuation of said one shutter.

4. The camera system of claim 1 wherein said camera system is of theself-developing type including means for spreading a processing fluidacross such sheet of photographic material responsive to such'sheet ofphotographic material being withdrawn from said camera system, saidsequence of steps includes the relative movement between said opticalsystems and said mounting means and operation of said actuating means tofirst record a pair of images when said mounting means is in said firstposition, then record a pair of images when said mounting means is in asecond position with respect to said optical systems and withdrawal ofsuch sheet of photographic material from said camera system subsequentto the relocation of said mounting means in said first position, andsaid indicating means additionally includes means responsive tooperation of both said shutter means when said mounting means is in saidsecond location, and to relative movement to relocate said mountingmeans in said first position for indicating to an operator that suchsheet is to be withdrawn.

5. A camera system comprising: a pair of optical systems forrespectively transmitting image carrying rays along a pair of exposurepaths so as to form a pair of images of a given size at a focal plane;means for mounting a sheet of photographic material in said focal plane,such photographic sheet being at least four times said given size;selectively operable shutter means for unblocking and then blocking eachof said exposure paths, said shutter means including a pair of shutterspositioned in operative relationship respectively with each of saidoptical systems; manually operative means for achieving relativemovement between said optical systems and said mounting means tOSequentially locate first and second areas of such sheet of photographicmaterial in operative relation to said optical systems whereby suchfirst area may be first exposed to record a pair of images thereon and,after relative movement has been effected between said optical systemsand said mounting means, such second area may be exposed to record apair of images thereon; selectively operable means for actuating saidshutter means to substantially simultaneously or sequentially unblockand then block each of such exposure paths when one of such first andsecond areas ofsuch sheet is located in operative relation to saidoptical systems so as to record a pair of images on such one area; andmeans responsive to the actuation of said pair of shutters to block andunblock both said exposure paths when such one area is located in suchone operative position for indicating to an operator that he shouldeffect relative movement between said optical system and said mountingmeans.

6. The camera system of claim 5 wherein said indicating means includesmeans for actuating one of said shutters simultaneously with, orsubsequent to, the other of said shutters, and said indicating means isresponsive solely to actuation of said one shutter.

7. The system of claim 6 for use with an electrical power source, saidindicating means is a normally inoperative electrical indicator, andsaid actuating means includes means for coupling said indicator means tosuch source responsive to actuation of only said one shutter wherebysaid indicator is rendered operable only upon actuation of both saidshutters.

8. The camera system of claim 5 wherein said indicating means comprisesinstructional indicia.

9. The camera system of claim 5 wherein said indicating means comprisesa light source.

10. The system of claim 5 wherein said actuating means includes aselectively operable actuator member configured for actuating saidshutters responsive to the operation of said actuator member by thecamera operator and manually operable shutter mode selection means forcoupling either both of said shutters to said actuator member so as toprovide a first mode of actuation of both said shutters responsive to asingle operation of said actuator member or a second mode of sequentialoperation of said shutters responsive to repeated operation of saidactuator member.

11. The system of claim 10 for use with an electrical power source andwherein: said indicating means is an electrically operable indicator;said shutters are electrically operable; said shutter selection meansincludes a first network configured for simultaneously conducting firingsignals to both said shutters and said indicator, a

second network configured for sequentially conducting firing signals toeach of said shutters in a predetermined order wherein a firing signalwill be conducted to said indicator and to one of such shutterssubsequent to conduction of the preceding firing signal to the other ofsaid shutters, and a selector switch for coupling either said first orsecond network to said actuator member; and said actuator memberincludes switch means for coupling such power source to said selectorswitch so as to produce such firing signals responsive to operation ofsaid actuator member.

1. A camera system comprising: a pair of optical systems forrespectiVely transmitting image carrying rays along a pair of exposurepaths so as to form a pair of images of a given size at a focal plane;means for mounting a sheet of photographic material in said focal plane,such photographic sheet being at least four times said given size;selectively operable shutter means for unblocking and then blocking eachof such exposure paths; means for actuating said shutter means tosubstantially simultaneously or sequentially unblock and block each ofsuch exposure paths when either a first or second area of suchphotographic sheet is located in operative relation to said opticalsystems; means for achieving relative movement between said opticalsystems and said mounting means to sequentially present such first andsecond areas of such sheet of photographic material to said opticalsystems whereby such a first area may be first exposed to record a pairof images thereon and, after relative movement has been effected betweensaid optical systems and said mounting means, such second area may beexposed to record a second pair of images thereon, the normal operationof said camera system being devised to commence with said mounting meansin a first given position with respect to said optical systems andinvolving a predetermined sequence of steps performed by an operator toproduce a pair of images on each such first and second areas of suchphotographic sheet, said sequence of steps including one step ofoperating said shutter actuating means so as to record a first pair ofimages and a subsequent step of effecting relative movement between saidoptical systems and said mounting means following the operation of saidshutter means; and means responsive to the performance by the operatorof said one step for indicating to the operator that said subsequentstep is to be taken by him in conforming with said predeterminedsequence of steps.
 2. The camera system of claim 1 wherein said shuttermeans includes a pair of shutters, and said actuating means includesmeans for actuating said shutters, and wherein said means for indicatingis responsive to actuation of both said shutters.
 3. The camera systemof claim 1 wherein said actuating means includes means for actuating oneof said shutters simultaneously with, or subsequent to, the other ofsaid shutters and wherein said indicating means is responsive solely toactuation of said one shutter.
 4. The camera system of claim 1 whereinsaid camera system is of the Self-developing type including means forspreading a processing fluid across such sheet of photographic materialresponsive to such sheet of photographic material being withdrawn fromsaid camera system, said sequence of steps includes the relativemovement between said optical systems and said mounting means andoperation of said actuating means to first record a pair of images whensaid mounting means is in said first position, then record a pair ofimages when said mounting means is in a second position with respect tosaid optical systems and withdrawal of such sheet of photographicmaterial from said camera system subsequent to the relocation of saidmounting means in said first position, and said indicating meansadditionally includes means responsive to operation of both said shuttermeans when said mounting means is in said second location, and torelative movement to relocate said mounting means in said first positionfor indicating to an operator that such sheet is to be withdrawn.
 5. Acamera system comprising: a pair of optical systems for respectivelytransmitting image carrying rays along a pair of exposure paths so as toform a pair of images of a given size at a focal plane; means formounting a sheet of photographic material in said focal plane, suchphotographic sheet being at least four times said given size;selectively operable shutter means for unblocking and then blocking eachof said exposure paths, said shutter means including a pair of shutterspositioned in operative relationship respectively with each of saidoptical systems; manually operative means for achieving relativemovement between said optical systems and said mounting means tOSequentially locate first and second areas of such sheet of photographicmaterial in operative relation to said optical systems whereby suchfirst area may be first exposed to record a pair of images thereon and,after relative movement has been effected between said optical systemsand said mounting means, such second area may be exposed to record apair of images thereon; selectively operable means for actuating saidshutter means to substantially simultaneously or sequentially unblockand then block each of such exposure paths when one of such first andsecond areas of such sheet is located in operative relation to saidoptical systems so as to record a pair of images on such one area; andmeans responsive to the actuation of said pair of shutters to block andunblock both said exposure paths when such one area is located in suchone operative position for indicating to an operator that he shouldeffect relative movement between said optical system and said mountingmeans.
 6. The camera system of claim 5 wherein said indicating meansincludes means for actuating one of said shutters simultaneously with,or subsequent to, the other of said shutters, and said indicating meansis responsive solely to actuation of said one shutter.
 7. The system ofclaim 6 for use with an electrical power source, said indicating meansis a normally inoperative electrical indicator, and said actuating meansincludes means for coupling said indicator means to such sourceresponsive to actuation of only said one shutter whereby said indicatoris rendered operable only upon actuation of both said shutters.
 8. Thecamera system of claim 5 wherein said indicating means comprisesinstructional indicia.
 9. The camera system of claim 5 wherein saidindicating means comprises a light source.
 10. The system of claim 5wherein said actuating means includes a selectively operable actuatormember configured for actuating said shutters responsive to theoperation of said actuator member by the camera operator and manuallyoperable shutter mode selection means for coupling either both of saidshutters to said actuator member so as to provide a first mode ofactuation of both said shutters responsive to a single operation of saidactuator member or a second mode of sequential operation of saidshutteRs responsive to repeated operation of said actuator member. 11.The system of claim 10 for use with an electrical power source andwherein: said indicating means is an electrically operable indicator;said shutters are electrically operable; said shutter selection meansincludes a first network configured for simultaneously conducting firingsignals to both said shutters and said indicator, a second networkconfigured for sequentially conducting firing signals to each of saidshutters in a predetermined order wherein a firing signal will beconducted to said indicator and to one of such shutters subsequent toconduction of the preceding firing signal to the other of said shutters,and a selector switch for coupling either said first or second networkto said actuator member; and said actuator member includes switch meansfor coupling such power source to said selector switch so as to producesuch firing signals responsive to operation of said actuator member.